I'm just doing a quick and dirty database thing using DB_File and reading up on it, http://perldoc.perl.org/DB_File.html gives examples of flags which can be attached to the tie() function: 

tie %A, "DB_File", undef, O_CREAT|O_RDWR, 0666, $DB_HASH ;

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Now I know what the 0666 is that's how would do it with dbmopen() but I don't know what those flags are. Obviously they mean "create" and "read-write" etc?

Where do these flags come from, where are they documented? How come they can be used as well as Unix permissions like 0666?

In reply to What are O_RDWR and O_CREAT and why does Perldoc assume I know this already? by Cody Fendant

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